To reduce obesity and thus promote healthy food choices, front-of-pack (FOP) labels have been introduced. Though FOP labels help identify healthy foods, their impact on actual food choices is rather small. A newly developed so-called swipe task was used to investigate whether the type of label used (summary vs. nutrient-specific) had differential effects on different operationalizations of the "healthier choice" measure (e.g., calories and sugar). After learning about the product offerings of a small online store, observers (N = 354) could, by means of a swipe gesture, purchase the products they needed for a weekend with six people. Observers were randomly assigned to one of five conditions, two summary label conditions (Nutri-Score and HFL), two nutrient (sugar)-specific label conditions (manga and comic), or a control condition without a label. Unexpectedly, more products (+7.3 products)-albeit mostly healthy ones-and thus more calories (+1732 kcal) were purchased in the label conditions than in the control condition. Furthermore, the tested labels had different effects with respect to the different operationalizations (e.g., manga reduced sugar purchase). We argue that the additional green-labeled healthy products purchased (in label conditions) "compensate" for the purchase of red-labeled unhealthy products (see averaging bias and licensing effect).
Keywords: Nutri-Score; averaging bias; calorie; food label; healthy food; licensing effect; sugar.